1. Field of the Invention
This invention generally relates to automatic systems for horizontally segmenting lines of text and then displaying the line segments. More specifically, this invention relates to a proportional spacing system which effects the display of line segments based upon the location of a cursor and beginning with whole characters.
2. Description of the Prior Art
The scrolling of text up and down in a vertical direction on the face of a display device has been known and used for some time. Also, the automatic scrolling or segmenting of text and other information in the horizontal direction is considered old. Considered new as far as this invention is concerned is a horizontal segmenting display system which can be used for efficiently handling text and other information made up of standard and proportional width characters. As far as the display of text made up on only standard width characters is concerned, no unsurmountable problems have been encountered. This is because the characters and spaces adjacent the left edge of a display segment will always be vertically aligned. When text made up of proportional width characters is considered though, a problem exists in generating partial characters to effect proper relative placement in the vertical direction. Up to now, there has been no known economical way to handle partial characters adjacent the left edge of the display. This problem is solved with the system of this invention in that partial characters are replaced with equivalent width spaces. The resultant is a ragged left edge, but the characters are aligned vertically as they would be printed. Also, the system of this invention is structured such that both proportional and standard width characters can be readily handled. With this being the case, a scale line made up of standard width characters and symbols can be displayed along with text made up of proportional width characters. Therefore, the display of a corresponding segment of the scale line in standard width characters and symbols will provide an operator with a page location reference means equivalent to a standard typewriter scale.